TW448709B - Low-thermal expansion circuit board and multilayer circuit board - Google Patents

Abstract

A low-thermal expansion circuit board comprising an insulating layer made of an organic polymer having thereon a wiring conductor for bare chip mounting, wherein the wiring conductor is an iron-nickel-based alloy layer having a copper layer on at least one side thereof; and a low-thermal expansion multilayer circuit board having a plurality of the low-thermal expansion circuit boards via an adhesive layer, the adhesive layer having through-holes filled with solder to connect the circuits layers.

Description

448709 V. Description of the invention (1) Field of the invention The present invention relates to a low thermal expansion circuit board and a low thermal expansion multilayer circuit board for mounting bare chips, which has a small thermal expansion coefficient and is therefore highly reliable. Background of the Invention With the recent trend of smaller size and higher performance of electronic equipment, semiconductor devices constituting electronic equipment and printed circuit boards for mounting devices are required to have reduced size and thickness, higher performance and higher Reliability. To meet these requirements, the pin insertion frame is replaced by a surface frame, and in recent years, a surface frame technology called a bare wafer pivot has been studied, in which non-packaged (bare) semiconductor components are Directly mounted on a printed circuit However, since it is mounted on a bare chip because it has a thermal expansion coefficient of 3 to ^^ ㈣ / .〇, a silicon wafer is directly mounted on a chip having a thermal expansion coefficient of 10 to 20 卯 "Begging: brush the circuit board due to thermal expansion Differences in stress generate stress, which can damage the reliability. For example, stresses such as flip-chip bonding can cause joints to break, which can lead to defective electrical connections. I have reduced the thermal stress, and people have implemented a kind of adhesive called underfill that fills the gap between the mounted semiconductor component and the printed circuit board. With the help of a knife, people can add it to the right before the right-hand side. Ying Miaoli: In order to absorb the printed circuit board itself and the multi-layer printed circuit board of the winding layer (No. -A + 297560). However, taking this step gradually (凊 "sufficient." To obtain further improved reliability to reduce printed electricity: board

Page 5 448709 V. Description of the invention (2) The thermal expansion coefficient itself is indispensable. On the one hand, Jp_A_61 — 212096 illustrates a multilayer circuit board including an insulating layer and a wiring conductor alternately formed thereon, and if desired, a solder pad is formed on the top layer of the Fe ~ Ni alloy by light etching. Materials, substrates, insulation layers and wiring conductors are combined under pressure to form a monolithic laminate under heat. The disclosed technique has the following disadvantages. In the case of using copper as a wiring conductor, it is difficult to reduce the thermal expansion coefficient of the entire circuit board to the level of silicon, because the elastic modulus of copper is much larger than those using polyimide resin as an insulating layer. Wiring systems are formed by thin metal film formation technologies such as vacuum deposition and sputtering, which have increased productivity and incurred increased costs. The formation of a solder pad by photoetching followed by photolithography requires complicated steps. On the other hand, increasing the 1/0 pin count of the semiconductors to be installed has increased the purity of the road boards in Xuxiang. Polymerization method, & Contained on the substrate: Or both sides' alternately gather the insulating layer of the photosensitive resin and deposit or deposit by bonding: a conductive layer formed to produce a multilayer circuit board. The agglomeration method has disadvantages because the production method is complicated and includes multiple steps. The production volume is low, and it is necessary to report to JP ~ A-8-288649. Suggest a box of welfare # β ~ h. Including borrowing a distributor, etc., 廉 4 廉 a ώ ώ * ^ * n to cover the copper side of the% oxygen / glass laminate t into the convex portion of the conductive paste, force ^, ^ a L ^ The adhesive sheet and the copper foil are pressed against it, and these steps are repeated. This technology is not reliable in connection and resistivity, and the connection resistivity is far from 7 people, and it is hardly applied. ☆ Hongqu * wide-time disk is used for fine circuits. Moreover, it is a time-consuming method, and the compaction step must be performed. Zheng must repeat it as many times as the number of layers.

448 70 9 V. Description of the invention (3) The inventors of the present invention have discovered that the 3rd inquirer yellow and polyimide resin are related to the conventional technology, and the thermal expansion of steel as a wiring material is aimed at semiconductor components. Cause. It is often used as a wiring diode, which is called 丄 丄 ^ ^ ^ ^..... I. Copper is not only mainly composed of plates, but also especially organic materials that constitute the insulation layer, such as products & '! 酼K ffifc J Bfe IV H Ah ^ TS.-, Li, JJ j !, -l A fli The tree end has a large thermal expansion coefficient and a large elastic modulus, which increases the stress of win. Although copper is a kind of Excellent conductive materials, and ...% essential for expansion I Feng wiring material invention Summary The purpose of the present invention is to provide a low thermal expansion electric expansion multilayer circuit board which has a small thermal expansion coefficient and excellent ^^ low thermal expansion above the purpose It is based on a low thermal expansion circuit board, which contains ~ 1. Sin. The object is made, and there are wiring conductors on it for bare chip installation: machine polymerization where the wiring conductor contains an iron-nickel-based alloy layer is achieved in Gan, There is copper on at least one side of the mesh. The whole of the mesh is originally placed in the through hole and the through-hole conductor is achieved by laminating a layer with a low-mature expansion circuit at least because of the layer structure. Implementation of the invention 'multilayer circuit boards have many adjacent The entire surface of the adhesive layer between the boards is connected to the f-laminated 'adhesive layer' of adjacent upper and lower double-sided lightning traces. The adhesive layer contains a conductor made of solder, adjacent positions, and The electrical wiring is extensively studied. ^ The extensive research on the wiring of the surface circuit board, the inventors, etc. used a composite compound material, which has a low side of a H-nickel-based alloy alloy layer, to develop successfully-S 'advertising copper Layer provides reliable low thermal expansion

448709

5. Description of the invention (4) Expansion circuit board. It is the main reason for the large thermal expansion of the circuit board. It is directly formed in an iron-record-based alloy with a low thermal expansion coefficient and low stress on the thermal expansion of the wiring conductor. Therefore, the thermal expansion of electricity can be suppressed, so that the adhesion after the bare chip is mounted is changed. It is another reason for the large thermal expansion of the circuit board. The abrupt number of the insulation layer can be improved by using a pyromellitic acid double Anhydride (pyromeU L is a dianhydride, hereinafter referred to as ρημ), nt-bi-p-ammidine kacid (mt〇lidine, hereinafter referred to as m_TLD), and a small thermal expansion _ diaminodiphenyl ether (hereinafter One of the polyimide resins is reduced. Therefore, the electric power can be further enhanced. The insulating layer made of an organic polymer contains 11-nickel-based alloy Ge-hemp and iron. A ^ 网 无The core layer made of material can be used, and the thermal expansion coefficient of the low insulation layer can be further reduced. The low thermal expansion circuit board of the present invention is further reduced to provide an advantage of the multi-layer circuit board. Sectional view 'shows that the low thermal expansion circuit board according to the present invention is a low thermal expansion multilayer circuit board according to the present invention, which is a top view. &Quot; Example of FIG. 8 is a cross-sectional view of a three-layer sheet. = Is a three-layer sheet of FIG. 8 Section view, there is a pass In creating three-layer sheet is a sectional view of the pigsty g, a copper plated through hole to be ° is a sectional view of a three-layer sheet of FIG ίο with - a circuit pattern is formed

Page 8 48 70 9 V. Description of the invention (5) Two sides, that is, a double-sided circuit board. Fig. 12 is a cross-sectional view of the double-sided circuit board of Fig. 11, with-an adhesive sheet temporarily adhering to it. Fig. 13 is a cross-sectional view of the double-sided circuit board of Fig. 12, with solder bumps formed in the through holes of the adhesive sheet. Detailed description of the invention The low thermal expansion circuit board expected in the present invention means a circuit board having a thermal expansion coefficient lower than the thermal expansion coefficient by 10 to 20 ppm / t. The iron-nickel-based alloy that can be used in the present invention includes not only an iron-nickel binary alloy as long as the thermal expansion coefficient is kept low, but also contains other elements such as an iron-bromine alloy. The preferred Ni content of the Fe-Ni binary alloy ranges from · 31 to 50% by weight. »Beyond this range, the alloy will have an increased coefficient of thermal expansion and will have reduced bonding reliability F e _ N i -c 〇 alloy includes those with Ni / Co / Fe weight ratios of 29/16/55, 32/8/60, and 36/4/60, which are each under the trade name KV-2 by Sumitomo Special Metals Co., Ltd. , Supplied by KV-25 and Superinvar. The total thickness of the iron-nickel-based alloy layer is preferably 10% or more on the circuit board, and is greater than the total thickness of the copper layer (s). With thinner iron-nickel-based alloy layers, circuit boards will have increased thermal expansion coefficients and reduced reliability. The thickness of the circuit board is preferably 200 micrometers or less / wiring conductor for high-density mounting. An organic polymer that can be used as an insulating layer is appropriately selected from those well-known in the art, such as phenol resin, epoxy resin, polyester resin, polyisocyanate resin, poly-imide resin, polyether. Ketone resin, and polyimide resin.

88109501.ptd Page 9 448709 V. Description of the invention (6) If desired, the organic polymer material can be used with paper, glass cloth, glass mat, glass nonwoven fabric, Kev 1 ar fiber, and the like to form a composite Insulation. An insulating layer made of a polyimide resin prepared from PHDA, m-TLD, and DDE is preferred because of its small thermal expansion coefficient. Although and the molar ratio of DDE to PHD A ranges from 0 to 100 mol%, polyimide having a small thermal expansion coefficient can be obtained, but the thermal expansion coefficient decreases as the proportion of m-TLD increases. Particularly, when the proportion of the m-TLD is 50 to 100 mol%, the polyimide resin has a thermal expansion coefficient of 10 p p m / ° C or less, and this is suitable for accomplishing a thermal expansion coefficient of 10 to 20 ppm /. (: Or smaller circuit boards. Ceramic materials that can be used as the core layer of the insulating layer are suitably selected from those having a low thermal expansion coefficient, such as alumina, mullite, cordierite, silicon carbide, silicon nitride, Aluminum nitride, and zirconia. A method for producing a low thermal expansion (multilayer) circuit board according to the present invention will be exemplified with reference to the drawings. A circuit board precursor having a copper layer on one side thereof is prepared as follows, that is, a single Copper-clad laminated sheet. The first method shown in FIG. 1 includes metallizing an organic polymer layer (insulating layer) i by an appropriate combination of deposition, electroless plating, plating, etc. to form a Iron-record-based alloy layer 2 and a copper layer 3. The second method shown in Figs. 2 and 3 includes depositing, plating, coating, etc. A copper layer 6 is formed on both sides, a multilayer metal thread 7 is formed in advance as a wiring conductor, and an organic polymer layer 1 is formed on the surface of the multilayer metal foil 7 by, for example, casting. The third one shown in FIG. Method, including borrowing

448709 Five, the description of the invention (7) and thermal and pressure bonding of the multilayer metal foil 7 to the adhesive layer 82 shown in FIG. 2 to form an adhesive layer 8 on the organic polymer layer 1. The `` shown in FIG. 5 '' includes, for example, casting and heat and pressure bonding of an organic polymer 1 to 4 j_, an adhesive layer 8 to provide a fit to the multilayer metal foil 7 shown in FIG. 2, 8 ° The fifth method shown in FIG. 6 includes preparing an organic polymer multilayer metal foil 7 shown in FIG. 2, and an adhesive sheet 9, and etch field—the sheet 9 heat and pressure Bonding organic polymer layer 1 and multi-layer metallic adhesives, including five methods, as phenol resin, adhesive resin 8 and adhesive resin layer 8 or adhesive sheet 9, such as epoxy resin, benzene can be prepared according to Single-sided tree:, and polyamide resin. ίίΓ: Circuit board precursors, that is, double-sided copper clad laminates 黏 f: f cast adhesive layer or adhesive sheet, will-pair ::: 以-ΐϊί compound. 2. Via the surveying agent layer or adhesive sheet, layer ΐ: Λ overlay! Layer _7 is shown in the single-sided copper clad lamination ... machine poly = measures, double-sided steel clad lamination. On the side of the "fifth layer", it is also possible to obtain the two-step thermal and pressure bonding of the double-sided copper-clad laminate prepared by the early-side copper-clad laminate. As one of the first methods, " At 5 o'clock, the polymer layer 1 can be metallized on both sides to prepare an organic sheet. Β w Double-sided copper cladding is removed by heat and pressure through a cast adhesive layer or an adhesive # ^ ^ Organic polymer layer to the heart Fu Bajie 4. (0 insulation layer, instead of the organic polymer layer 1 prepared on each side of the layer, can be the same way as explained above> 7 work, and always be ready "" There is a core layer in Its insulation layer is copper clad) ΐ ^ pressure pressure step included

44β 709 V. Description of the invention (8) can be completed at the same time. A copper-clad laminate with a core layer over its insulating layer can be prepared by heat and pressure bonding, casting, and any other combination of metallization. By a conventional subtraction process, a circuit pattern is formed on a single-sided or double-sided copper-clad laminate. It can be made into a through hole and laminated with double-sided steel. In the case of forming a via hole with a double-sided copper-clad laminate having a conductive material (such as a metal) as the core layer, it is necessary to avoid electrical connection between the via hole and the metal core layer. That is, a through hole is made in advance to pass through a metal core layer, and a wiring conductor is provided on both sides of the composite insulating layer with the metal core layer. A through hole smaller than the metal core layer is made, and passes through the copper core concentrically with the through hole of the metal core. Overlay. Moreover, after forming the through hole, both surfaces of the circuit board and the inner wall of the through hole can be plated with copper. A method of producing the multilayer circuit board of the present invention will now be explained. As mentioned above, with the known multi-layer circuit board structure and known methods, it is difficult to produce all the requirements that meet the requirements of simple and economical methods, reliability of connection in the circuit layer, and narrowing of the pitch. The present invention addresses this point. Unlike the conventional agglomeration method, the simplification of the lamination step and the improvement of economic efficiency in the present invention are achieved by simultaneously bonding a plurality of double-sided circuit boards together under heat and pressure. The electrical connection in the circuit layer is achieved by a conductor made of solder to achieve high reliability. The conventional connection is achieved by conductive paste. Lamination can temporarily attach a double-sided circuit board to the double-sided circuit board by temporarily adhering an adhesive with a through-hole in the correct position, temporarily placing another double-sided circuit board in the correct position, and finally Under heat and pressure, the laminated sheets are bonded to form a whole body. Adhesive sheet suitable for preparing multilayer circuit boards, including a piece of thermosetting

5. Description of the invention (9) Properties or thermoplastic resins, such as epoxy resin, phenol resin, polyimide resin, and polyimide resin. Polyimide resins are preferred because of their reliability. In the case that the adhesive sheet contains a thermosetting component, it should be temporarily adhered to the double-sided circuit board in a state of harmony, so that when the subsequent pressure adhesion to the multi-layer circuit board, curing may not be carried out to cause loss of re-establishment. Degree of adhesion. The thickness of the adhesive sheet is preferably 10 micrometers or more for obtaining workability and unevenness of leveling circuits, and preferably 200 micrometers or less for reducing multilayer circuit boards. Of the total thickness. Through holes can be made by known techniques such as drilling and punching. Solder bumps can be formed from solder paste by electroplating or printing. Solder paste printing is preferred because of its simplicity. The size of the solder balls in the solder paste is 100 microns or less, preferably 50 microns or less, and more preferably 20 microns or less. The solder composition is designed to have an appropriate melting point depending on the type of insulation layer and the necessity for mounting. As long as the adhesive sheet can show sufficient adhesion (500 g / cm or larger), the pressure bonding temperature can be higher or lower than the melting point of the solder. At a temperature above the melting point of the solder, a metal joint is formed. Even at temperatures below the melting point of the solder, electrical connections are made between the circuit layers. " Fig. 7 shows an embodiment of a multilayer circuit board of the present invention. Drawing number 11 is a double-sided circuit board composed of an insulating layer 12, which is made of a polyimide resin ^, and a metal v is formed from (wiring conductor) 1 3 on both sides. The bimetal method 1 3 series = —iron-nickel-based alloy foil 14 and copper foil 15 as outer layers. In this particular embodiment, two double-sided circuit boards are laminated to provide a circuit board with four circuit layers. Each double-sided circuit board 1 has a through hole 1 and a plated copper 'to provide-a plated through hole 16 through which a double metal foil 13 is electrically connected 443709 V. Description of the invention (10) Connection. A double-sided circuit board is bonded via a polyimide adhesive layer 17 and is electrically connected to each other by a conductor 18 made of solder. The multilayer circuit board of FIG. 7 is produced as follows. A polyimide precursor varnish was applied to an iron-nickel-based alloy hall 14, dried, and transferred to a polyimide layer 12 to prepare a two-layer sheet. The two-layer and two-layer sheets are pressure-bonded to face each other through a pressure-sensitive adhesive sheet and the polyimide layer under heat to obtain the three-layer sheet 20 shown in FIG. 8. A through hole Ua is drilled in the three-layer sheet 20 at a predetermined position, and the through hole 11a and the alloy foil 14 are plated with copper by electroless plating and electroplating on both sides. The laminated sheet 21 is covered with a double-sided steel as shown in the drawing, wherein the reference number 15 indicates the copper drop formed by the copper keying. A circuit pattern is made on the bimetallic drop 13 (consisting of alloy solution 14 and copper junction 15), and the circuit board 11 shown in FIG. N is prepared. A previous one—the through hole 17a is made as a stick at a predetermined position. 17. Adhere to the side of the double-sided circuit board with heat force: The through hole 17a is accurately positioned as shown in Fig. 12. The adhesive film ^ 7 in Fig. I 2 corresponds to The adhesive layer 17 in Fig. 7. As shown in Fig. 13, the through hole

Li: board printing, filled with n through a metal mask formed by solder bumps 18:-Tsui sole preparation 'Yes'-double-sided circuit boards with through holes in predetermined positions are bonded with heat and pressure to the other A double-sided board 11 ′ having soldering blocks 丨 8 is used to obtain the whole 4-layer circuit board shown in FIG. 7, in which two double-sided circuit boards 11 are electrically connected via soldering blocks 丨 8. Μ = In the above embodiment, the wiring conductor, that is, the bimetals 3 composed of the iron alloy museum 14 and = 5, has a small thermal expansion coefficient, resulting in a multi-layer circuit: having excellent and reliable lifetime. Moreover, the method is simple and economical. The present invention will now be illustrated in more detail with reference to examples, but please understand that the present invention

Page 14 ϋ 70 9 V. Description of the invention (11) It is not considered to be limited to these examples. Example 1 A polyimide precursor varnish (making ρ-phenylenediamine and 3, 31, 4, 41-linked The ρ ο 1 yamic acid varnish prepared by the reaction of phenylbiphenyltetracarboxylic acid dianhydride in N-methylmethyl 11-pyrrolidone is applied to — to — brocade — iron (by weight, 4 2/58% ) Alloy (coefficient of thermal expansion: 5ppm / ° C) made of 10 micron thick metal foil, dried, and treated at 400 ° C in a nitrogen atmosphere for 1 hour to form polyfluorene

The amine was 10 microns thick. The resulting two-layer sheet was given at 2000. 〇 Adhesion to another two-layer sheet prepared with a polyimide layer facing each other via a 35 micron thick polyimide adhesive sheet (SPB-035A produced by Nippon Steel Chemical Co., Ltd.) At the same time, a pressure of 40 kg / cm 2 was applied to prepare a three-layer tablet. Copper was then deposited on each side of the two-layer sheet by electroless plating and electroplating to a thickness of 9 microns to prepare a double-sided copper-clad laminate. Example 2 Except for changing the gold (coefficient of thermal expansion: 1 1 port. Jin Cheng wound to nickel / iron = 36/64% by weight in the same way as in Example 1 ppm / C), a double-sided copper-clad laminated system Prepared in real Example 3. In addition to changing the metal man, / 8/60% (5 gold content of thermal expansion injury to nickel / cobalt / iron = 32 by weight to match the value in Example 1. 10 ppm / ㈠, the double-sided steel-clad laminated system ^ 4 was prepared in the same way. Except the use of a poly break: Π ·

Amine adhesive tablets including PMDA, m-TLD and DDE

Page 15 448709 V. Description of the invention (12) A double-sided copper-clad laminate was prepared in the same manner as in Example 1 except for a molar ratio of 50/40/100. Example 5 In addition to a 30 micron thick nickel / iron (42/58% by weight) alloy layer, a 35 micron thick polyimide adhesive sheet (spB-035A) was used on both sides instead of polyimide Except for the adhesive sheet, a double-sided copper-clad laminate was prepared in the same manner as in Example 1. Example 6 Except for a 50 micron thick nickel / iron (3 6/6 4% by weight) alloy layer, a 35 micron thick polyimide thick polyimide adhesive sheet (3 {^ _ 0 3 5 A), instead of a polyimide adhesive sheet, a double-sided copper-clad laminate was prepared in the same manner as in Example 2. Example 7 In addition to a 200-micron-thick aluminum nitride sheet (coefficient of thermal expansion: 4.3 mm / mm) (:), there is a 35-micron-thick polyimide adhesive sheet (SPB-035A) on both sides, Instead of a polyimide adhesive sheet, a double-sided copper-clad laminate was prepared in the same manner as in Example 1. Example 8 except that the through hole was at a predetermined position (see Figure 9) and had a diameter of 0.2 mm to be Drilled through a three-layer sheet (before steel plating), as shown in Figure 10, a double-sided copper clad laminate with through holes was prepared in the same manner as in Example 1. The copper foil was A circuit pattern was formed on one side to prepare a double-sided circuit board as shown in Fig. 11. A polyimide adhesive (SPB-035A) previously prepared at a predetermined position and having a through-hole of 0.2 mm in diameter, was prepared in 180 ° C at 30 kg / cm2,

Page 16 448709 V. Description of the invention (13) '' Squeeze to one side of the double-sided circuit board for 30 minutes while positioning it accurately as shown in FIG. 12. Solder paste (SnBRA produced by Nippon Spice K. K., -3 A M Q; shock point: 2 60 C) was printed on an adhesive sheet through a metal mask screen, and the through holes were filled with the solder paste. After reflowing at 2900 ° C, the flux is washed off to form a solder bump as shown in Figure 13. The resulting board with solder bumps was pressure bonded to another separately prepared double-sided circuit board with through holes, and simultaneously positioned at 2000 ° C and 30 kg / cm2 for 1 hour to obtain a 4-layer circuit board. The two double-sided circuit boards are electrically connected through the solder bumps. Comparative Example 1 A polyimide precursor varnish prepared by reacting p-phenylenediamine and 3, 31, 4, 41-biphenylbiphenyltetracarboxylic dianhydride with N-fluorenylpyrrolidone Polyamic acid varnish) was applied to 18 micron thick rolled copper foil, dried, and treated at 400 ° C for one hour in a nitrogen atmosphere to form a polyimide layer having a thickness of 10 micron. The resulting two-layer sheet was bonded to another at 20 ° C. under a pressure of 40 kg / cm 2-again facing each other with a polyimide layer through a 35 micron thick polyimide adhesive sheet. (SPB_〇35A) The two-layer sheet prepared for 1 hour to prepare a double-sided copper-clad laminate. Comparative 眚 2 丨 2 except for epoxy-silver solder paste, screen printing instead of solder paste, and heat The cured outer 4-layer circuit board was prepared in the same manner as in Example 8. The thermal expansion coefficients of the double-sided copper-coated man-made sheets prepared in Examples 1 to 7 and Comparative Example 1 were in the temperature range from room temperature (2 5 t) Measured until 2 0 0 = t. The results obtained are shown in Table 1 below. Table 1

8810950] .ptd Page 17a 48 70 9 V. Explanation of the invention (14) Coefficient of thermal expansion (ppm / ° C) Example 1 7. 0 Example 2 4.2 Example 3 3.5 Example 4 5.8 Example 5 5.5 Example 6 3.0 Example 7 5.0 Comparison Example 1 17.0 As can be understood from Table 1, the circuit board according to the present invention has a very small coefficient of thermal expansion, which proves suitable for bare chip mounting. The multilayer circuit boards obtained in Example 8 and Comparative Example 1 were subjected to a thermal cycle test to evaluate the reliability of the block connection. Therefore, at 100% of the joints of the two samples, immediately after thermal and pressure bonding, they showed satisfactory electrical conductivity. After giving 500 thermal cycles of 125 ° 30 minutes to -50 minutes 30 minutes, 100% of the joints in Example 8 became conductive, while 10% of the joints in Comparative Example 2 were joined. Defective electrical connections are shown. The multilayer circuit board of the present invention has now proven to be excellent in reliability. 7. Although in Example 8, the through-hole 17a of the adhesive sheet 17 was filled with solder paste by screen printing, it can be completed by a dispenser or a transfer application. Although the present invention has been described in detail and with reference to specific examples thereof, those skilled in the art will appreciate that various changes and modifications can be made therein without

4 48 7 0 9 Case No. 88109501_year a. Amendment 5. Description of the invention (15) Deviation from its spirit and scope. Component number description 1 Organic polymer layer 2 Iron-nickel-based alloy layer 3 Copper layer 5 Iron-nickel-based alloy foil 6 Copper layer 7 Multi-layer metal foil 8 Adhesive layer 9 Adhesive sheet 11 Double-sided circuit board 11a Through hole 12 Insulating layer 13 Bimetal foil 14 Iron-nickel-based alloy foil 15 Copper network 16 Plated through hole 17 Adhesive sheet 17a Through hole 18 Solder block 20 Three layer sheet 21 Double-sided copper clad laminated sheet

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Claims (1)

^ 48709 VI. Scope of patent application 1. A low thermal expansion circuit board, comprising an insulating layer made of an organic polymer, and a wiring conductor thereon for bare chip mounting, wherein the wiring conductor is a copper layer An iron-nickel-based alloy layer on at least one side. 2. For example, the low thermal expansion circuit board of the scope of patent application, wherein the insulating layer is a polyimide resin prepared from pyromellitic dianhydride, m-ditoluidine, and diaminodiphenyl ether. Made. 3. For example, the low-heat-expanded printed circuit board of the scope of application for patent, wherein the insulating layer has a core made of an iron-town-based alloy or a ceramic material. 4. A multi-layer circuit board having many low thermal expansion circuit boards, each including an insulating layer made of an organic polymer, and a wiring conductor thereon for bare chip installation, wherein the wiring conductor is a copper layer having a copper layer on the wiring conductor. An iron-record-based alloy layer on at least one side. 5. For multi-layer circuit boards under the scope of patent application, many double-sided circuit boards are integrally laminated with an adhesive layer interposed between all adjacent circuit boards, and the adhesive layer has through-holes adjacent to each other. The positions of the wiring conductors of the upper and lower double-sided circuit boards, and the through hole contains a conductor made of solder, and the wiring conductors of adjacent double-sided circuit boards are electrically connected by it. Page 20